Manchester City face an anxious wait to see if Frank Lampard faces a spell on the sidelines after the midfielder came off in their 2-0 win over Hamburg in Abu Dhabi.
Lampard was forced off in the first half of the friendly in the United Arab Emirates, which City won courtesy of goals from Stevan Jovetic and Edin Dzeko.
City later confirmed the former England midfielder sustained the problem in the warm-up, according to boss Manuel Pellegrini.
The club tweeted: "LAMPARD UPDATE: Pellegrini confirms Lampard was injured in the warm up and taken off as a precaution.''
City are already without two attacking midfielders, with Yaya Toure at the African Nations Cup and Samir Nasri ruled out for up to a month with a calf strain, so any injury for Lampard would be ill-timed.
The 36-year-old, who has scored seven goals in 21 games for the Premier League champions, was expected to play a significant role in Toure's absence.
City host Middlesbrough in the FA Cup on Saturday before visiting Lampard's former club Chelsea in the Premier League seven days later.
Top scorer Sergio Aguero, who has only made one start after a month out with a knee injury, came on for the final 25 minutes in the Hazza Bin Zayed Stadium.
City, who are on a warm winter break, also had 17-year-old forward Thierry Ambrose stretchered off.